DETROIT -- General Motors is replacing its head of engineering and will divide its vehicle engineering organization into two divisions in a shakeup that the company says will improve quality and safety in the wake of its recall crisis.

John Calabrese, 55, vice president of global vehicle engineering since April 2011, will retire, GM said in a statement.

GM said it will divide vehicle engineering into two organizations: Global Product Integrity and Global Components and Subsystems.

Ken Morris, 47, now executive director of chassis engineering at GM, will head the product integrity unit. Ken Kelzer, 51, who now leads powertrain engineering in Europe, will take over the components and subsystems group.

The changes are effective immediately.

GM product chief Mark Reuss said the restructuring is a direct outgrowth of GM’s review of the ignition-switch problem.

He said Calabrese's departure "is in no way connected" to the company's internal investigation into its failure to recall the faulty switch sooner.

GM is under fire for its handling of the defective ignition switches, which has been linked to 13 deaths in 2004-07 small cars. The company has acknowledged that its engineers flagged the problem as early as 2001 but did not recall the cars until February.

On a conference call with reporters, Reuss said the new structure will help GM flag potential safety problems such as the defective ignition switch more quickly. He said the product integrity division will include a team of GM's "best" engineers to review vehicles for safety compliance at regular intervals as they are being developed.

Reuss said GM has used the same process for years to improve steering, ride and handling and other performance characteristics.

He said engineers will take a more holistic approach to identifying the root cause of problem parts and examine more closely how flaws in individual components could affect other systems in the vehicle.

"It would have expedited a whole bunch of things," Reuss said of the structure now being implemented, "with experts that are vehicle-driven, subsystem experts, instead of just parts-driven experts."

GM also has added 35 "product investigators" -- up from about 20 previously -- in charge of analyzing reports of crashes, customer complaints, lawsuits and other data relayed to the company that could indicate a safety problem.

GM CEO Mary Barra told a congressional panel this month that part of GM's failure to fix the faulty ignition switch pointed to a communication breakdown inside GM, where "there was information at one part of the company and another part of the company didn't have access to that."

The team of about 55 product investigators, which will be inside the product integrity division, would help to eliminate those communication barriers, GM executives said. They will report to global safety chief Jeff Boyer, who was appointed in March and had been reporting to Calabrese; he will now report to Morris.

Product integrity chief Morris said that having the beefed up investigation unit is one of the "fundamental differences" of the new engineering structure to help GM prevent a future safety flaw from going undetected.

GM will connect "the dots on all of the information that we gather," Morris said, and not be "siloed so that that information doesn’t get transferred from one spot to another."

CEO Mary Barra announced the creation of the Global Product Integrity group during a speech in New York last week. She described it as "a new way of developing vehicles," which would take the same approach that has helped GM improve the driving performance of its vehicles in recent years and apply it to improve safety.

The product integrity organization will include the new global vehicle safety group that GM created in February, led by Jeff Boyer. That unit also will oversee supplier quality and include vehicle, powertrain and electrical-systems engineering; vehicle performance; industrial engineering and validation, GM said.

Boyer had been reporting to Calabrese. He will now be part of the product integrity unit headed by Morris.

The components and subsystems group led by Kelzer will include engineering operations, components development and advanced vehicle development.

“A vehicle is a collection of 30,000 individual parts. Fully integrating those parts into cohesive systems with industry-leading quality and safety is key in this customer-driven business,” Reuss said in a statement.

Morris, who has been at GM for 25 years, most recently has been responsible for the design and execution of fuel systems, suspensions, steering, brakes and other systems on GM vehicles. Before that, he was executive director for global vehicle performance.

GM said the product integrity organization will use "advanced analysis tools and processes to flag and prevent issues during vehicle development." It also will analyze field reports "to react quickly to safety and product quality issues customers may experience."

GM is under fire for its handling of a faulty ignition switch in mid-2000s small cars that has been linked to 13 deaths. GM has acknowledged that its engineers flagged the problem as early as 2001 but did not recall the cars until February.

Before Kelzer's powertrain assignment in Europe, he was global vehicle chief engineer for rear-wheel-drive and performance cars.

Calabrese started with GM in 1981 and has served in a number of executive-level positions in engineering and purchasing. GM said he will stay at the company through August to help the transition.

“Under John’s leadership, GM has developed industry-leading vehicles in practically every segment in which we compete,” Reuss said. "We thank John for his many contributions -- and I thank him for his friendship -- and wish him the best."